#881 PDS3/4 should support read of subset of the data

[Jeremy Faden]

It would be nice if you could read a subset of a file, like you can with CDF and NetCDF files. I am reading the Times, then I could figure out which records to read, then read just those. This would reduce the amount of code needed (no lines to take subset, also avoiding repeat which might be forgotten for one parameter).

tr= getParam('timeRange', '2018-091 10:45 to 10:55' )

uri= 'https://pds-ppi.igpp.ucla.edu/data/JNO-J_SW-JAD-5-CALIBRATED-V1.0/DATA/$Y/$Y$j/ELECTRONS/JAD_L50_HRS_ELC_TWO_DEF_$Y$j_V$v.LBL' 

T= getDataSet( uri + '?DIM0_UTC', tr, monitor.getSubtaskMonitor('Read data file'))
PA= getDataSet( uri + '?DIM3_PITCH_ANGLES', tr )
EN= getDataSet( uri + '?DIM1_E', tr)
DEF= getDataSet( uri + '?DATA', tr )

r= where( within( T, tr ) )
T= T[r]
DEF= DEF[r]
PA= PA[r]
EN= EN[r]

[Jeremy Faden]

tr= getParam('timeRange', '2018-091 10:45 to 10:55' )

uri= 'https://pds-ppi.igpp.ucla.edu/data/JNO-J_SW-JAD-5-CALIBRATED-V1.0/DATA/2018/2018091/ELECTRONS/JAD_L50_HRS_ELC_TWO_DEF_2018091_V02.LBL' 

T= getDataSet( uri + '?DIM0_UTC', tr, monitor.getSubtaskMonitor('Read data file'))
r= extent(where( within( T, tr ) ))
T= T[r[0]:r[1]]

PA= getDataSet( uri + '?DIM3_PITCH_ANGLES[%d:%d]' % (r[0],r[1]) )
EN= getDataSet( uri + '?DIM1_E[%d:%d] % (r[0],r[1]) )
DEF= getDataSet( uri + '?DATA[%d:%d]' % (r[0],r[1]) )